html, body {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
}
body{
    background-image: url(../image/bg.jpg);
    background-size: cover;
    background-position: calc();
    font-size: 14px;
    color: #4d4d4d;
    font-weight: 300;
}